/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.dolphinscheduler.plugin.alert.dingtalk;

import org.apache.dolphinscheduler.alert.api.AlertResult;
import org.apache.dolphinscheduler.common.utils.JSONUtils;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.StringUtils;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * <p>
 * https://open.dingtalk.com/document/robots/custom-robot-access
 * https://open.dingtalk.com/document/robots/customize-robot-security-settings
 * </p>
 */
public final class DingTalkSender {

  private static final Logger logger = LoggerFactory.getLogger(DingTalkSender.class);
  private final String url;
  private final String keyword;
  private final String secret;
  private String msgType;

  private final String atMobiles;
  private final String atUserIds;
  private final Boolean atAll;

  private final Boolean enableProxy;

  private String proxy;

  private Integer port;

  private String user;

  private String password;

  DingTalkSender(Map<String, String> config) {
    url = config.get(DingTalkParamsConstants.NAME_DING_TALK_WEB_HOOK);
    keyword = config.get(DingTalkParamsConstants.NAME_DING_TALK_KEYWORD);
    secret = config.get(DingTalkParamsConstants.NAME_DING_TALK_SECRET);
    msgType = config.get(DingTalkParamsConstants.NAME_DING_TALK_MSG_TYPE);

    atMobiles = config.get(DingTalkParamsConstants.NAME_DING_TALK_AT_MOBILES);
    atUserIds = config.get(DingTalkParamsConstants.NAME_DING_TALK_AT_USERIDS);
    atAll = Boolean.valueOf(config.get(DingTalkParamsConstants.NAME_DING_TALK_AT_ALL));

    enableProxy = Boolean.valueOf(config.get(DingTalkParamsConstants.NAME_DING_TALK_PROXY_ENABLE));
    if (Boolean.TRUE.equals(enableProxy)) {
      port = Integer.parseInt(config.get(DingTalkParamsConstants.NAME_DING_TALK_PORT));
      proxy = config.get(DingTalkParamsConstants.NAME_DING_TALK_PROXY);
      user = config.get(DingTalkParamsConstants.NAME_DING_TALK_USER);
      password = config.get(DingTalkParamsConstants.NAME_DING_TALK_PASSWORD);
    }
  }

  private static HttpPost constructHttpPost(String url, String msg) {
    HttpPost post = new HttpPost(url);
    StringEntity entity = new StringEntity(msg, StandardCharsets.UTF_8);
    post.setEntity(entity);
    post.addHeader("Content-Type", "application/json; charset=utf-8");
    return post;
  }

  private static CloseableHttpClient getProxyClient(String proxy, int port, String user, String password) {
    HttpHost httpProxy = new HttpHost(proxy, port);
    CredentialsProvider provider = new BasicCredentialsProvider();
    provider.setCredentials(new AuthScope(httpProxy), new UsernamePasswordCredentials(user, password));
    return HttpClients.custom().setDefaultCredentialsProvider(provider).build();
  }

  private static CloseableHttpClient getDefaultClient() {
    return HttpClients.createDefault();
  }

  private static RequestConfig getProxyConfig(String proxy, int port) {
    HttpHost httpProxy = new HttpHost(proxy, port);
    return RequestConfig.custom().setProxy(httpProxy).build();
  }

  private AlertResult checkSendDingTalkSendMsgResult(String result) {
    AlertResult alertResult = new AlertResult();
    alertResult.setStatus("false");

    if (null == result) {
      alertResult.setMessage("send ding talk msg error");
      logger.info("send ding talk msg error,ding talk server resp is null");
      return alertResult;
    }
    DingTalkSendMsgResponse sendMsgResponse = JSONUtils.parseObject(result, DingTalkSendMsgResponse.class);
    if (null == sendMsgResponse) {
      alertResult.setMessage("send ding talk msg fail");
      logger.info("send ding talk msg error,resp error");
      return alertResult;
    }
    if (sendMsgResponse.errcode == 0) {
      alertResult.setStatus("true");
      alertResult.setMessage("send ding talk msg success");
      return alertResult;
    }
    alertResult.setMessage(String.format("alert send ding talk msg error : %s", sendMsgResponse.getErrmsg()));
    logger.info("alert send ding talk msg error : {}", sendMsgResponse.getErrmsg());
    return alertResult;
  }

  /**
   * send dingtalk msg handler
   *
   * @param title   title
   * @param content content
   * @return
   */
  public AlertResult sendDingTalkMsg(String title, String content) {
    AlertResult alertResult;
    try {
      String resp = sendMsg(title, content);
      return checkSendDingTalkSendMsgResult(resp);
    } catch (Exception e) {
      logger.info("send ding talk alert msg  exception : {}", e.getMessage());
      alertResult = new AlertResult();
      alertResult.setStatus("false");
      alertResult.setMessage("send ding talk alert fail.");
    }
    return alertResult;
  }

  private String sendMsg(String title, String content) throws IOException {

    String msg = generateMsgJson(title, content);

    HttpPost httpPost = constructHttpPost(
        org.apache.commons.lang3.StringUtils.isBlank(secret) ? url : generateSignedUrl(), msg);

    CloseableHttpClient httpClient;
    if (Boolean.TRUE.equals(enableProxy)) {
      httpClient = getProxyClient(proxy, port, user, password);
      RequestConfig rcf = getProxyConfig(proxy, port);
      httpPost.setConfig(rcf);
    } else {
      httpClient = getDefaultClient();
    }

    try {
      CloseableHttpResponse response = httpClient.execute(httpPost);
      String resp;
      try {
        HttpEntity entity = response.getEntity();
        resp = EntityUtils.toString(entity, "UTF-8");
        EntityUtils.consume(entity);
      } finally {
        response.close();
      }
      logger.info("Ding Talk send msg :{}, resp: {}", msg, resp);
      return resp;
    } finally {
      httpClient.close();
    }
  }

  /**
   * generate msg json
   *
   * @param title   title
   * @param content content
   * @return msg
   */
  private String generateMsgJson(String title, String content) {
    if (org.apache.commons.lang3.StringUtils.isBlank(msgType)) {
      msgType = DingTalkParamsConstants.DING_TALK_MSG_TYPE_TEXT;
    }
    Map<String, Object> items = new HashMap<>();
    items.put("msgtype", msgType);
    Map<String, Object> text = new HashMap<>();
    items.put(msgType, text);

    if (DingTalkParamsConstants.DING_TALK_MSG_TYPE_MARKDOWN.equals(msgType)) {
      generateMarkdownMsg(title, content, text);
    } else {
      generateTextMsg(title, content, text);
    }

    setMsgAt(items);
    return JSONUtils.toJsonString(items);

  }

  /**
   * generate text msg
   *
   * @param title   title
   * @param content content
   * @param text    text
   */
  private void generateTextMsg(String title, String content, Map<String, Object> text) {
    StringBuilder builder = new StringBuilder(title);
    builder.append("\n");
    builder.append(content);
    if (org.apache.commons.lang3.StringUtils.isNotBlank(keyword)) {
      builder.append(" ");
      builder.append(keyword);
    }
    byte[] byt = StringUtils.getBytesUtf8(builder.toString());
    String txt = StringUtils.newStringUtf8(byt);
    text.put("content", txt);
  }

  /**
   * generate markdown msg
   *
   * @param title   title
   * @param content content
   * @param text    text
   */
  private void generateMarkdownMsg(String title, String content, Map<String, Object> text) {
    StringBuilder builder = new StringBuilder(content);
    if (org.apache.commons.lang3.StringUtils.isNotBlank(keyword)) {
      builder.append(" ");
      builder.append(keyword);
    }
    builder.append("\n\n");
    if (org.apache.commons.lang3.StringUtils.isNotBlank(atMobiles)) {
      Arrays.stream(atMobiles.split(",")).forEach(value -> {
        builder.append("@");
        builder.append(value);
        builder.append(" ");
      });
    }
    if (org.apache.commons.lang3.StringUtils.isNotBlank(atUserIds)) {
      Arrays.stream(atUserIds.split(",")).forEach(value -> {
        builder.append("@");
        builder.append(value);
        builder.append(" ");
      });
    }

    byte[] byt = StringUtils.getBytesUtf8(builder.toString());
    String txt = StringUtils.newStringUtf8(byt);
    text.put("title", title);
    text.put("text", txt);
  }

  /**
   * configure msg @person
   *
   * @param items items
   */
  private void setMsgAt(Map<String, Object> items) {
    Map<String, Object> at = new HashMap<>();

    String[] atMobileArray =
        org.apache.commons.lang3.StringUtils.isNotBlank(atMobiles) ? atMobiles.split(",")
            : new String[0];
    String[] atUserArray =
        org.apache.commons.lang3.StringUtils.isNotBlank(atUserIds) ? atUserIds.split(",")
            : new String[0];
    boolean isAtAll = Objects.isNull(atAll) ? false : atAll;

    at.put("atMobiles", atMobileArray);
    at.put("atUserIds", atUserArray);
    at.put("isAtAll", isAtAll);

    items.put("at", at);
  }

  /**
   * generate sign url
   *
   * @return sign url
   */
  private String generateSignedUrl() {
    Long timestamp = System.currentTimeMillis();
    String stringToSign = timestamp + "\n" + secret;
    String sign = org.apache.commons.lang3.StringUtils.EMPTY;
    try {
      Mac mac = Mac.getInstance("HmacSHA256");
      mac.init(new SecretKeySpec(secret.getBytes("UTF-8"), "HmacSHA256"));
      byte[] signData = mac.doFinal(stringToSign.getBytes("UTF-8"));
      sign = URLEncoder.encode(new String(Base64.encodeBase64(signData)), "UTF-8");
    } catch (Exception e) {
      logger.error("generate sign error, message:{}", e);
    }
    return url + "&timestamp=" + timestamp + "&sign=" + sign;
  }

  static final class DingTalkSendMsgResponse {
    private Integer errcode;
    private String errmsg;

    public DingTalkSendMsgResponse() {
    }

    public Integer getErrcode() {
      return this.errcode;
    }

    public void setErrcode(Integer errcode) {
      this.errcode = errcode;
    }

    public String getErrmsg() {
      return this.errmsg;
    }

    public void setErrmsg(String errmsg) {
      this.errmsg = errmsg;
    }

    @Override
    public boolean equals(final Object o) {
      if (o == this) {
        return true;
      }
      if (!(o instanceof DingTalkSendMsgResponse)) {
        return false;
      }
      final DingTalkSendMsgResponse other = (DingTalkSendMsgResponse) o;
      final Object this$errcode = this.getErrcode();
      final Object other$errcode = other.getErrcode();
      if (this$errcode == null ? other$errcode != null : !this$errcode.equals(other$errcode)) {
        return false;
      }
      final Object this$errmsg = this.getErrmsg();
      final Object other$errmsg = other.getErrmsg();
      if (this$errmsg == null ? other$errmsg != null : !this$errmsg.equals(other$errmsg)) {
        return false;
      }
      return true;
    }

    @Override
    public int hashCode() {
      final int PRIME = 59;
      int result = 1;
      final Object $errcode = this.getErrcode();
      result = result * PRIME + ($errcode == null ? 43 : $errcode.hashCode());
      final Object $errmsg = this.getErrmsg();
      result = result * PRIME + ($errmsg == null ? 43 : $errmsg.hashCode());
      return result;
    }

    @Override
    public String toString() {
      return "DingTalkSender.DingTalkSendMsgResponse(errcode=" + this.getErrcode() + ", errmsg=" + this.getErrmsg() + ")";
    }
  }
}
